Valve reseating tool



H. G. MILLER Feb. 23, 1932.

` VALVE RESEATING TOOL Filed Feb. l2, 1930 Patented Feb. 23, 1932 SATS 'UNIT TEN u Pfiff i HAR-RY Gr.' Minima, or' DENVER, conoscano `VMNE :aEsnA'rING Toor.

Application ineaY rebruarypiz, raso.v seriali No. 427,717.

Y necessary to employV af cutter that isguided by. means of a pilot which is rigidly Secured in'the guide opening of the vcylinder' block. Y 1)' The usual type'of internal combustion en- A ginesis providedV with guide openings which areof the proper diameter to receive the valve stem, and Vwith this type of engine, pilots like those shown and described in'my copending application 310,354, tiled October 4E,- 1928, are employed. Owing to the small diameter of the guide opening the pilots are rather flexible with the result that they do not hold the cutter firmly in concentric relation with the guide opening and unless a special type ofcutter is employed, it is very difficult, if'not impossible, to get the Vvalve seats concentric with the guide opening. Y In at least one type of internal combustion engine now employed in connection with automobiles, the .guide openingsfare of much Vlarger diameterthan has vheretofore been employed and'are lined vby means of two semicylindrical, removableV bushings, whichcan be readilyremoved andwhich, therefore leaves an opening of considerable diameter, for the reception of the lower end ofthepilot.

.Located directly beneathV the guide'openings` are ,valve tappets thatV` are axially 40 aligned with the openings and with' the cylindrical valve port. p

Itis the object of this inventiontoproducea pilot that is specially, designed for Y use in connection with enginesofthe above k vmentioned ,constructionyand which, briefly described, consists of a cylindrical vsteel VbarV Vhavin' a central portion ofadiame'ter equal tothe diameter of the guideopening and whose lowerfportion' is cylindricalfand of slightly smaller diameter than thefcentral valve seat.; i

Vters are held in place. f

portion. Asleeve' is slidablyconnected with the lower end Aof the pilot andthe opening in the lower end of this sleeve isV of the proper size to receive the 'upper `end. ofthe valvev tappet. The upper end of thepilot is` p referably, although not necessarily, ofla smaller diameter than the central portion and is Lpro` vided -with an inwardly extending axial opening that is'threaded for VVthe'reception of a screw. -This screw can be rotated for '60 the purpose-ofadjustment and serves as a stop for the Vcutter in av manner that'will hereinafterv appear. 1 The lower endY of the central portion is provided with a few. turns of square threads that serve as cleaners'for 65 removing foreign matterl from the guide opening when the pilot is inserted therein. f

HavingV thus vbriefly described' 'the invention, the same will -now be described in detail `and for thispurpose referencefwillbe had to the accompanying drawings in which the preferred embodiment has lbeen illustrated andin which: f Fig. .l is a vertical section'taken through' a valve port and, its associated lguide open- ,75

ingV and which also showsthe valve tappet and my improvedY pilot in place;:=

Fig. 2 is a section similar to that .shown in Fig. l and shows a slightly -modifiedV form of cutter attached to the pilot; n Y.

` Fig. 3 is a-view partly insection and partlyv in elevation and Vshows a micrometer Vdevice attachedtothescrew for the purpose of rotating the latter through va .predetermined anale; i 185 Fig. 4 is a section taken on line H, Fig. 8;

Fig". 5 is a section taken on line 5e5,.Fig. 1;

Fig. (r3-isa view looking inV thedirection of l arrow 6, Fig. 2 and shows a bottom plan'view 4 of the-roughing cutter;

Fig. 7 is a section taken on line 7 7, Fig. 6;

Fig. 8 is a sectionjtaken on line 8'1-8, Fig. '6, and shows the cutter/employed for cutting the rig. 9 is a' @aanrekenen 111161949, Fig., e 55"" fand' shows the seventy-five'degree cutter; yand Fig. ylOris a 'section Vtakenron line 10--10. Fig. 6 and shows the manner in which the cuti In drawings reference numeral 'l desig- 100 "perfect alignment.

nates a cylinder bloc-k of the type employed in connection with internal combustion engines. These blocks are provided with a plurality of valve ports 2 that are in axial alignment with guide openingsV 3. Located directly beneath and axially aligned with the guide openings are valve tapp-ets 4. Y c

The=upper ends of the valve ports are provided with inclined conical surfacesv 5 that form valve seats and these must be very accurately formed so as to" be concentric with the guide openings and so as to have a predetermined angle and for the lbest results the valve seat must befabsolutelyconcentric,l

with the guide opening. Y.

` `fIn themanufacture of the-engine the valve ports,`the kguide openings andthe openings iniwhich the valve tappets are mounted, are usually formedby a single tool and are thereforeconcentric one with the other and in After the'engine has'been in use'for some time, the valve seats become worn o r corroded 1to1' fhold them in vaxial alignment vwith the openings, lfh'ave provided a pilot which I will now describe. 'This pilot is preferably constructed-of steel-andhas a central cylindrical fportion that'wis of the-same diameter as the openings 3 so that afterthe pilot has been inserted in place it -will fitthe opening so as to prevent any lateral movement of theV Vpilot with respect to the engine block.v .The lower end Vof the cylindrical'surface 6 ris preferably `provided with a few turns off square `threads 7. ThesethreadsV serveV as" cleaners forl the 1purpose'ofremo'ving foreign matter from the ginner surfaceV of openings S'whenthe pilot is put into place. Beneath 'thev central cylindrical section 6. the pilot is formed with a cylindrical surface 8 whose diameter is pref` Y erably equal. to the root diameter of the threads?. The lower end `of section S adapted to rest on the upper end of a'valve tappetinthe'manner shown in l and is provided with a sleeve 9r that has a sliding fit "withthelower end of the pilot and the lower en'd'ofwhoseopening is of such 'size'that it acylindrical sectionV lO'that is usually of Asmaller diameter. Vthanl the `central section.

lThe upper endgof thepilot is provided` with lan axial openinglllithat is threadedfor vthe isy Jabove p the central section 6 theA pilotisformed with reception of a screw f1.2. The opening and the screw are preferably provided with threads of one-fortieth of an inch pitch so that when the screw is rotated one-twentyfth of a turn, it will move longitudinally one-thousandth of an inch. provided with agraduation mark 13 that extends parallel with the axis ofthe pilot and this inturn is provided Vwith a plurality of transverse marks 14 spaced one-fortieth of'an inch apart.V "Theupper surface of the head 15 of thevscrew is provided with a flat surface and has an opening 16 extending downwardly thereinto.- For the purpose of rotating the screw I have provided a cap 17 that canbe-slipped over thescrew andover. the upper endof the pilot.v` 'This cap is provided with a pin `18 that extends into the opening 16 in the manner shown in FigQB. The lower end-of the cap is provided with an inclined surface 19'whose lower edgehasa plurality ofgraduation marks 20. The circumference ofthe cap is divided into twenty-live eq'ual spaces by thegraduation. marks and when vthe cap isgrotated through an angle equal to the distance-.between `two adjacent marks, the screw .will be moved one-thousandth ofl an inch inthe direction of the length of the pilot.v *The` purpose of this micrometerl adjustment will be more'fully explained as Ythe description-proceeds. When the pilotis to be used itis put in place in the manner shown inzFig. l and will then be heldin rigid alignment with the kseveral openings. If desired a nut 21 can be appliedto the-threads 7`for the Vpurpose of clamping the pilot in place,

but Ythis is. not vconsidered necessary andis usuallydispensedwith as the use of this nut consumes a considerable amount of timel VAfter the pilot has beenl put intogplace, a f z Iroughing cutter is applied to it in themanner shown in F 2. For'thebest results vthis cutter-must "be constructed in the Vmanner shownin'ligs 6 to 10,from which it will be seen that it consists of a ring-like portion 22 L vthat is provided with four radial openings y, g/and z. The depth of these openings varies, that of openingm being greater than that ofo'penings y and that of y beingfgreater. than; that of opening e. .Located in the opening a' is a fly cutter 23, whose cutting edge 24 makes an angle offlifteen degrees witha plane perpendicularto the axis of rotation. Cutters 25 that are located invopenings g/ have cuttingedges 26 that make an angle .of 45 l degrees with the plane of rotation and cut- -ter27, that isllocated in opening a, has a cutftingedge 28 that makes an angle 'of seventyfive degrees with the plane of'rotation. These cutters, are lheldin place by means of screws 29v for the reception of lwhich threaded open- VVVings SOhave been provided adjacent leach of the radial openings inthe manner shown-'in `Fig. 10. .These screws are provided with headshaving flat shoulders 31 that are adapti edto engage the under surface of the cutters and hold them in place. Gutter 22 is'secured. to the lower end ofv a sleeve 33 and is held in position on ,thissleeve by friction. The upper Vend of the sleeve is closedr bymeans ofa threaded plug 36 `which isadapted to Vengage the upper fiat surface ofhead L15'. Plug'is preferably provided-with a 4.0 pitch'thread and has a slot 32` that can be enga-ged byla screw driver. Lock nut -Sltfholds thelp'lug in adjusted position. The upper section 37 of sleeve 38 is hexagonal and can be rotated by means of any special tool that is suitable This tool has not' been tion. When the cutter is rotated the iy cutters will cut three surfaces which have been designated respectively asa, and c. The surface ZJ is the one with which the valve cooperates andis usually. inclined atan angle of forty-live degrees. The depth of the cut is determined by the position of screw 15 and therefore if the valve tappet corresponding to the valve seat to be cut is always moved to its lower position before the pilot isput in place,`the distancefrom the valve seat Zi to the tappet will always be exactly the saine and it is therefore possible to so cut the valve seats that all of the valve stems can be made exactly of the saine length. If for any -purpose it is found desirable to cut one of the valve seats to a greater depth than the others, the exact difference can be determined 'by means of the micrometer attachment shown in Fig. 3 and the exact amount to be cut off from the corresponding valve stem can therefore be determined and in this way the fitting of Vthe valves is greatly simplified. the usual practice of fitting valve stems, the distance from the valve seats to the valve tappets is never the saine as it is determined by chance and therefore each valve stem must be separately adjusted Whichrequires a large amount of time and labor that can be almost entirely dispensed with when my valve reseating tool is employed.

After the roughing tool has been employed,

a finishing cutter like that shown in Fig. .1" vand designated by reference numeral 38 is used. This finishing cutter is of the ordinary construction and `is secured tothe tapered end 39 of a sleeve 40 that is substantially like that shown in Fig. 2. The depth to which this tool canv cut is determined by the position of the screw 12 in the manner explained in connection with the roughing cutter or by the position of plug 35.

lt is usually preferable to adjust-the posif .tion of the finishing cutter by means of the plug 35 that can be rotated by means of a cap Y like that indicated by numeral 17 in Fig. 8

and by means of which-the exact values of the adjustments can be determined.

To prevent accidental rotation of screw 12,

Vthe latter is split by two diametrical cuts and the. pilot by means of a bayonet slot.

.spread so that it will press againstthe side i of the opening and .thereby produce sufficient p friction to prevent-it from rotating.-

.For inserting and removing the pilot applicant lhas, provided aspecial tool thatv has, not been'shown and which is connected with vF rom the above description it will be seen that I- haveproduced a valve reseating tCol that comprises a pilot of such yconstructioi'n that it-can be made yof fairly large diameter .y

guideopenings. These pilots are providedA with an .adjustable screw that can vbe accurately positioned-bymeans of a micrometer attachment and therefore, since the pilot rests on theupper end of the tappet,vthe'distance between'the valve seat andthetappet canal-y vvvays'be accurately determinedand if any.v

change in this distance'is made, the 'difference can be accurately measured and therely reduced. j i

Y. Having. Vdescribed the invention (what is claimed as new is: V `1 i l .i f

1.A`pilot for use in reseating valveseats in engine blocks-havingvalveseats concentric with guide openings,- saidpilot comprising a .steel-bar of. circula-rv cross section, the central portion ofthe bar. having a cylindrical sectionof substantially the vsaine diameter ,as the gjuidevopening, thellower end of the vpilot'being soformedfasto be supported on a valve tappet, a sleeve `slidablyv connected withr Vthe lowerV end thereof, fthe uppery end of thepilot havinggan vaxial threaded opening, a screw operatively associatedj with the .opening and a cutter ycarrying sleeve. connected `with the upper` end ofl thepilot, the

A9o 7 fore the work of'adjusting the valves is greatcutter carrying sleeve having means near 'its upper. end for engaging the upper endof the screw;

- 2. A1-,pilotfforuse .in reseatingfvalve seats in engine blocks having. valve .seats concentric withfgui'de openings, and valve tappets fin alignment with the guide openings, said .to be supported ontheupper end of a valve tappet afsleeveslidably secured thereto, the

115 .xpilotzcomprising a steel bar of circular :cross section,.the centralportion of-thebar having a cylindrical section of `substantially the same"l .diameter zas n the lguide. opening, the

opening intheilowenend ofthe sleeve be ing of theproper sizetolreceive the upper end of a vvalve tappet,fthe .upper end ofthevv pilot Vhaving ran axial i, threaded opening, a

.screw `oigi-eratively associated-with theopen- Wing and meansfor adjustingthe .screw to '.'any Vdesired angle, said-means comprising jcap having an'opening adapted tofreceive-l cn y less diameter thanl the central.portion,- the opening y,andv toyrest ony theupper end f the #corresponding valve tappet, a .the ypilot having a. central section of substantially the same diameter` as the-guide opening and having its lower endprovided with a sleeve, the openingin the lower end of the sleeve being of sufficient size to-'reeeive the upper end of a lvalve tappet and adapted yto make connectioii between the; pilot andthe upper end fof the valve tappet.

' Intestimony VwhereofI aix my. signature.

HARRY G. MILLERQ .v

lower end of the central kportion rhavingal few turns of square threads, the; pilot having itslower end formed so as to be supportedon the upper end ofva. valvertappeta` cylindrical sleeve slidably secured thereto,` .the lower endof the Yopening intheV sleeve being ofthe samezdianieter as ythe valve tappet and adapted to receivethe upper end of theiatter, theupper end ofi-the pilot havi l' ing an axial opening adapted 4,to receive an adjusting' sciew andra serewwin said openlng.

e 4. A device for reseating valve seats :in o

cylinder blocks having valve seatsconoentric. with guide openings located between l:the

valve seats and the valve Ytappets,: comprisinga pilot having a central cylindrical. section of thefsame-diameter as theguide open- -ing and having its lower end so formed as to be supportedoii the upper end of a valve -tappet, an adjusting lscrew secured inan opening inthe other-end of. tlie"pilot,-.a

sleeve enclosing thescrew Land a portion :of

the pilot, a cutter .secured'to-the sleeve and a bearing member locatedin .the upper end of the sleeve and' adapted to engage the end of -the screwv and `to :limitltliev downward movement of the sleeve `and cutter.

' .5. A pilot lfor use? in .reseating valve seats in cylinder blocks having axially aligned valve tappets,"l guide :openings valve' seats and valve tappets below the guide openings, comprising a bar of circular cross-section, the central portion consisting ofacylindrical section whose diameter is equal to the Vdiameter of the guide opening, the lower end-consisting of a cylindrical seotionof diameter smaller than vthat of the central sectionand -V so formed as to be supported on. avalve tappet, the lower end of the central section having a few turnsof threads, a sleeve 'slidably connected with the lower end of the pilot the n Y yopening in the lower end of the ksleeve being of' sufficient size to receive the upper end of a valve tappetytheotherend of thepilot having a threaded axial opening, and a screw rotatably secured in `theopening.

,-6.111 combination with aeylindei. block having axially aligned valve seats, "guide openings and valveV tappets, a pilot consisty ingvof a steel bar adapted to extendthrough the plane of the valveseat', through the guide 

